Method and Apparatus for User-Steerable Recommendations

ABSTRACT

Method and apparatus for transparent, steerable recommendations. A steerable recommender uses tag clouds including descriptive tags and associated weights to generate recommendations. Users may dynamically interact with the recommender via a user interface to steer the recommendations. A tag cloud for an item is displayed, items for which associated tag clouds are most similar to the displayed tag cloud are identified, and the items are displayed as recommendations. The strength of similarity of the items to the displayed tag cloud may be displayed. The user may modify a tag cloud, for example by changing the weight of a tag or by adding or removing a tag, and the recommendations may be automatically updated to reflect the modification. A recommended item may be selected to display the tag cloud corresponding to the item. A user may select a user interface element to request information on why a particular item was recommended.

BACKGROUND

The amount of content on the Internet is growing dramatically.Recommender technology is key to helping people find new, interestingand relevant items in this content. For example, music recommendationsystems are increasingly important in the ever-growing world of digitalmusic. A recommender is a tool that recommends one or more items to auser based on one or more provided criteria. Conventional recommenderstypically use some form of collaborative filtering that exploits thewisdom of the crowds to make recommendations of the form “people whobought X also bought Y.” A recommender using collaborative filteringgenerally relies on the names or titles of items to makerecommendations. Such a recommender, directed at music, may take thetitle(s) of music that a user has expressed interest in or purchased,look for other people who have purchased the same title(s), determineone or more other titles that the other people have purchased but theuser has not, and recommend one or more of the other titles to the user.

Conventional recommenders that rely on collaborative filtering generallydo not provide reasons as to why an item is recommended beyond “Otherpeople who selected item X also selected item Y.” Further, theseconventional recommenders typically provide limited ability to interactwith the recommender. A user receiving a bad recommendation may know areason why they do not like the recommendation, but the user is notprovided with a method to provide this information to the recommender,and even if they could, a collaborative filtering-based recommenderwould not know what to do with the information. In addition, theseconventional, collaborative filtering-based recommenders are generallynot steerable except by applying explicit ratings to items or byapplying filters on the metadata returned with the items. In theseconventional recommenders, providing a rating may affect futurerecommendations, but it is difficult to determine, and to explain, howone rating action will affect future recommendations.

SUMMARY

Embodiments of a method and apparatus for programmatically generatingtransparent, steerable recommendations are described. A recommender isdescribed that generates transparent, steerable recommendations. Thesteerable recommender uses meaningful words or phrases that aredescriptive of particular items to drive the recommendations, as opposedto conventional recommenders that rely on collaborative filtering. Usersmay dynamically interact with the recommender to steer recommendationstowards more relevant content, and thus may receive more personalizedand directed recommendations.

A steerable recommender may provide a user interface. The steerablerecommender may receive user input, via the user interface, specifying atag cloud. The tag cloud may include one or more tags and weights forthe tags. For example, a user, via the user interface, may requestrecommendations for items similar to a particular item that the userlikes. Alternatively, the user may simply select an item via the userinterface. In addition, a tag cloud for a particular item may bedisplayed on the user interface, and the user may modify the tag cloud,for example by interactively changing the weight of a particular tag, orby adding or removing a tag. As another alternative, the user may submita custom tag cloud not associated with any particular item to thesteerable recommender via the user interface. Other methods of acceptinguser input via a user interface specifying a tag cloud and relatedinformation are possible and contemplated. The user input may, but doesnot necessarily, cause the retrieval of information related to the tagcloud from information currently displayed on the user interface. Forexample, the user input may only identify an item, and the steerablerecommender may obtain the tag cloud and related information from a datastore that stores collected tag clouds for related items, or from someother location if the tag cloud is not in the data store. In oneembodiment, if there is no tag cloud for a specified item in the datastore, the recommendation engine may dynamically generate a tag cloudfor the item in response to the user input.

A set of items for which associated tag clouds are most similar to thespecified tag cloud may be identified. Information may be displayed, tothe user interface, identifying the set of items and indicatingsimilarity to the specified tag cloud. The displayed information mayinclude a set or list of items that are similar to the specified itemaccording to comparisons of the tag clouds, or a set or list of itemswhose tag clouds are similar to a specified custom tag cloud if the userhas submitted a custom tag cloud not related to a particular item. Avalue indicating the strength of the similarity to the specified itemmay be displayed with each item. At least a subset of the list of items,and the associated strength of similarity value, may be displayed to theuser interface. The user interface may include a scrollbar or other userinterface element that allows a user to view additional items on thelist if all the items cannot be displayed in the space provided.

In one embodiment, a user may select a displayed item in the list ofrecommended items, and the tag cloud for that item may then bedisplayed. The tag cloud may be displayed, for example, by displayingthe tags (descriptive words or phrases) in the tag cloud. The relativeweights of the tags may be indicated, for example by displaying tagswith higher weights at larger font sizes. In one embodiment, in responseto the user selecting an item from the list, in addition to displayingthe tag cloud for the selected item, the recommendation list mayautomatically be updated to display items recommended according to thetag cloud of the selected item. In one embodiment, a user may modify acurrently displayed tag cloud via the user interface, for example byinteractively changing the weight of a tag, or by adding or removing atag, and the list of recommended items may be automatically updated toreflect the user's modification of the tag cloud.

In one embodiment, a steerable recommender may receive user input, via auser interface to the steerable recommender, requesting information onwhy an item was recommended. In one embodiment, a user interface elementmay be associated with each item in the displayed list of recommendeditems. A user may select this interface element to request informationon why the particular item was recommended. Information may bedisplayed, to the user interface, indicating why the item wasrecommended in response to the user input. In one embodiment, sincerecommendations made by the steerable recommender are based on thesimilarity between a user-specified tag cloud and the tag clouds of therecommended item(s), a more detailed explanation of why an item wasrecommended may be provided by displaying how the two tag cloudsoverlap.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram that illustrates a networked environmentimplementation of a steerable recommender according to some embodiments.

FIG. 2 is a block diagram that illustrates an example systemconfiguration that provides a web service interface, and shows theinteraction between a web service client and a web service provider,according to some embodiments.

FIG. 3 is a block diagram that illustrates a steerable recommender and auser interface to the steerable recommender implemented on one device,according to some embodiments.

FIG. 4 is a block diagram that illustrates collecting item informationfor a steerable recommender, according to some embodiments.

FIG. 5 illustrates a method for constructing and maintaining a datastore of information for items including descriptive tags and tag cloudsfor the items according to one embodiment.

FIG. 6 illustrates a method for determining a set of recommended itemsfrom the descriptive information for a specified item, according to oneembodiment.

FIG. 7 illustrates a method for generating and displayingrecommendations in response to user input, according to one embodiment.

FIG. 8 illustrates a method for generating and displaying modifiedrecommendations in response to user input modifying a tag cloud,according to one embodiment.

FIG. 9 illustrates a method for displaying information as to why aparticular recommendation was made, according to one embodiment.

FIG. 10 graphically illustrates examples of tag clouds for severalexample artists according to one embodiment.

FIG. 11 shows an example of a tag cloud including overlapping or commontags for two artists in which the size of the font used for a tag isdetermined by the weight of the tag to visually indicate the strength ofthe overlap, according to one embodiment.

FIG. 12 illustrates an example of a steerable recommender user interfaceaccording to one embodiment.

FIG. 13 illustrates another example of a steerable recommender userinterface according to one embodiment.

FIG. 14 is a block diagram of a computing device, according to someembodiments.

While the system is described herein by way of example for severalembodiments and illustrative drawings, those skilled in the art willrecognize that the system is not limited to the embodiments or drawingsdescribed. It should be understood, that the drawings and detaileddescription thereto are not intended to limit the system to theparticular form disclosed but on the contrary, the intention is to coverall modifications, equivalents and alternatives falling within thespirit and scope of the present system as defined by the appendedclaims. The headings used herein are for organizational purposes onlyand are not meant to limit the scope of the description or the claims.As used throughout this application, the word “may” is used in apermissive sense (i.e., meaning having the potential to), rather thanthe mandatory sense (i.e., meaning must). Similarly, the words,“include”, “including”, and “includes” mean including, but not limitingto.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiments of a method and apparatus for programmatically generatingtransparent, steerable recommendations are described. A recommender isdescribed that generates transparent, steerable recommendations. Thesteerable recommender uses meaningful words or phrases that aredescriptive of particular items to drive the recommendations, as opposedto conventional recommenders that rely on collaborative filtering. Usersmay dynamically interact with the recommender to steer recommendationstowards more relevant content, and thus may receive more personalizedand directed recommendations. The steerable recommender may allow a userto interactively and dynamically explore a complex set of items. Thisinteractivity may lead to recommendations that are highly relevant andnovel. Unlike conventional recommenders, embodiments of the steerablerecommender, via the use of meaningful words and phrases, may provideexplanations as to why particular items were recommended, thus providingtransparency to the recommendations. This transparency may enhance thetrust that a user has in the recommender. The transparency andinteractivity of the steerable recommender may help the user in findingnew and interesting items, and may also be more engaging and enjoyablefor the user than conventional recommenders.

An item, as used herein, refers to a particular instance of a categoryof items for which recommendations may be generated. Categories of itemsfor which recommendations may be generated using embodiments mayinclude, but are not limited to: artists (musicians, authors, painters,poets, directors, etc.), artistic works (albums, songs, books,paintings, poems, movies, cable/television shows, etc.), scholarly orother works (white papers, research papers, scientific publications,publications such as electronic or paper magazines or newspapers, etc.),consumer products (computers, cars, personal electronics, appliances,computer software products, etc.), retail or service businesses(restaurants, retail stores, online retailers, brick-and-mortar oronline service businesses, etc.), institutions (schools, hospitals,etc.), service persons (doctors, plumbers, lawyers, mechanics, etc.),and Web sites (blogs, discussion boards, etc.). In general,recommendations for any category of item for which descriptive tags maybe generated and acquired may be generated and manipulated byembodiments of the steerable recommender. While embodiments may beapplied to any such category of item, embodiments are described hereinthat are directed at music and musical artists by way of example.

An issue with conventional collaborative filtering-based recommendersmay be referred to as the “cold start” problem. A fairly large base ofusers and number of transactions may be required to make the “Otherpeople who bought item X also bought item Y” recommendations provided bythese types of recommenders useful for a web enterprise. Thus, atstartup of such a recommender, there may not be enough data to makemeaningful and useful recommendations for at least some items. Thisissue may be referred to as the “cold start” problem. Using descriptivetags rather than collaborative filtering for generating recommendationsallows embodiments of the steerable recommender to collect meaningfuldescriptive information for items from network or other sources asdescribed above, and thus to make meaningful and useful recommendationseven for a new recommender that does not have many users.

Other issues with conventional collaborative filtering-basedrecommenders may include a lack of sales information for new items.Thus, new items, especially if not popular sellers, may tend to not getrecommended or get low-priority recommendations when in fact these newitems may include items that would be of interest to the user.Similarly, rarely purchased or not-as-popular items tend to getunder-recommended or not recommended by conventional recommenders.Furthermore, very popular items may tend to be over-recommended orrecommended for items not very similar to the item on which therecommendation is based. Using descriptive tags rather thancollaborative filtering for generating recommendations allowsembodiments of the steerable recommender to collect meaningfuldescriptive information for items from network or other sources asdescribed above, even for new and rarely purchased or not-as-popularitems, and thus to include meaningful and useful recommendations forthese items when a tag cloud submitted by a user closely matches the tagclouds for these items. Furthermore, since the recommendations are notbased on popularity, very popular items may not be over-recommended orrecommended for items not very similar to the item on which therecommendation is based.

Embodiments of the steerable recommender allow a user, via the userinterface component of the steerable recommender, to find similar itemsto an item or to a set of items according to the descriptiveinformation, or tag cloud. In embodiments, the recommendation enginecomponent of the steerable recommender may use vector space distancecalculations, for example the cosine distance between the tag clouds, todetermine item similarity for items in the data store. In oneembodiment, the results of a find similar operation may be filtered by arecommendation engine component of the steerable recommender to optimizerelevance, novelty and familiarity in accordance with preferences of theuser.

One embodiment may allow a user to construct a tag cloud independent ofany particular item and use this tag cloud as input to the steerablerecommender. This tag cloud may describe the parameters that areimportant to the user. The steerable recommender may use the findsimilar technique to find items that are similar to the tag cloud, andreturn the similar items (potentially filtered) as recommendations tothe user.

In some embodiments, user may interact with a tag cloud via the userinterface component of the steerable recommender. For example, in oneembodiment, the user may dynamically adjust the weights of tags in thetag cloud interactively, receiving updated recommendations after everyadjustment. This allows the user to steer the recommender towards itemsthat are of interest to the user. By allowing a user to control andsteer a recommender, embodiments of the steerable recommender may allowusers to find items that are more relevant to the user's particularinterests or tastes than do conventional recommenders. Examples ofsteerable recommender user interfaces are provided in FIGS. 6 through 8.

As an example directed at musical artists, a user may like the artistJimi Hendrix. The user may go to an online music retailer that uses aconventional recommender that uses collaborative filtering. The user maypose a query ‘find more music like Jimi Hendrix.’ The user receivesrecommendations for artists such as Janis Joplin and the Doors(representing the 60s and psychedelia aspects of Hendrix), as well asEric Clapton, Stevie Ray Vaughan, and Steve Vai (representing the guitarvirtuoso aspects of Hendrix). However, the user may be more interestedin the guitar playing aspects of Hendrix, and less interested in otheraspects such as psychedelia. However, the conventional, collaborativefiltering recommender gives the user little or no control over what isrecommended.

Using an embodiment of the steerable recommender directed atrecommendations for musical artists, the user may obtain or generate atag cloud for Jimi Hendrix and use that as the starting point for arecommendation query. In one embodiment, the tag cloud may berepresented on a display screen such that higher weighted tags in thecloud are shown in a larger font. The user may use the cursor controldevice to adjust or manipulate the tags in the tag cloud. For example,the user may, via the user interface, add new tags, remove tags, orincrease or decrease the weights of the tags via a cursor control deviceclick-and-drag to resize the tags. The user may make the weight of a taggo negative, indicating that the user wants to avoid items with thattag. The user may use the cursor control device to make the‘psychedelia’ tag smaller. Immediately, the list of recommended artistsis updated and artists with strong ‘psychedelia’ tags are demoted in thelist of recommendations. The user then uses the cursor control device tomake the ‘guitar’ tag larger. Again, the recommended artists areimmediately updated to emphasize artists with strong guitar tags. Theuser decides that he prefers more contemporary music, so the userdeletes the ‘60s’ tag from the tag cloud and adds a ‘00s’ tag to thecloud. Again, the recommendations update reflecting the user'sinterests.

As another example, a user may like a wide variety of music. Byexamining artists that the user likes to listen to and the associatedplay counts, an embodiment of the steerable recommender mayautomatically build a tag cloud that represents the user's taste, oralternatively may allow the user to construct the personal tag cloud.The steerable recommender may then use this tag cloud to makerecommendations for the user. However, the user may not always be in themood for the same kinds of music. While working, the user may prefermusic with no vocals; while driving, the user may prefer upbeat music;while reading, the user may prefer quiet music. The user may use thesteerable recommender along with the user's personal tag cloud to findmusic that the user may like that fits the user's particular mood. Forinstance, to find music for work, the user may start with the personaltag cloud and deemphasize the vocal tags. The steerable recommenderreturns music recommendations that the user may like and that matchesthe tags that are more heavily weighted in the personal tag cloud, butwith few vocals. The user may save this tag cloud and reuse it whendesired to get a new set of music to listen to while working.

FIG. 1 is a block diagram that illustrates a networked environmentimplementation of a steerable recommender according to some embodiments.In these embodiments, a server 102 coupled to a network 100 may host aninstance of recommendation engine 110 and a recommendation data store112. Network 100 may, for example, be a local area network, a wide areanetwork, or the Internet. An example computer system that may be used asa server 102 is illustrated in FIG. 14. Device 104 includes an instanceof steerable recommender user interface 114. Device 104 may, forexample, be representative of a personal desktop or portable computersystem, or of any of various types of personal electronic devices withnetwork connectivity such as a portable digital audio file player (e.g.,an MP3 player), personal digital assistant (PDA), or cell phone. Anexample computer system that may be used as a device 104 is illustratedin FIG. 14. Steerable recommender user interface 114 may, for example,be implemented as a page or pages displayable on or by a web browser.Alternatively, steerable recommender user interface 114 may beimplemented as or on one or more display pages of a network-enabledclient software program.

In one embodiment, server 102 may provide a web site accessible toclient(s) via web browsers on device(s) 104. The web site may display asteerable recommender user interface 114 as or on one or more pages ofthe web site. The user may submit requests for recommendations to thesteerable recommender via the user interface 114. A user may, forexample, specify an artist name or a song via the steerable recommenderuser interface 114, may submit a tag cloud, may modify a tag in adisplayed tag cloud, or may provide some other input to the steerablerecommender via the user interface. The user input may be sent to therecommendation engine 110 on server 102 via the Internet 100 in one ormore messages. Recommendation engine 110 may then process the requestand return information to the device 104 via Internet 100. To processthe request, recommendation engine 110 may access recommendation datastore 112 to find recommendations by comparing the tag clouds of itemsin the data store 112 with a tag cloud provided by the user via the userinterface 114. The information may include new or modifiedrecommendations. The steerable recommender user interface 114 may beupdated to reflect the information, for example by displaying the new ormodified recommendations.

While FIG. 1 shows one device 104, there may be multiple devices 104each including a steerable recommender user interface 114. Further,while FIG. 1 shows one server 102, one instance of recommendation engine110, and one recommendation data store 112, there may be multipleservers 102, multiple instances of recommendation engine 110 andmultiple data stores 112. Further, different data stores 112 may beimplemented that store recommendation information for differentcategories of items, or different recommendation information for thesame category of item.

While FIG. 1 illustrates an example networked environment configurationin which a server 102 hosts an instance of recommendation engine 110 anda recommendation data store 112, and a device 104 includes an instanceof steerable recommender user interface 114, in some embodiments, asteerable recommender may be implemented as a web service. FIG. 2 is ablock diagram that illustrates an example system configuration thatprovides a web service interface, and shows the interaction between aweb service client and a web service provider, according to someembodiments. In this example, a web service interface 206 may beimplemented on a server 202 coupled to Internet 200. This server 202 maybe referred to as a web service provider. Server 202, or alternativelyone or more other servers coupled to server 202, may include one or moreinstances of recommendation engine 210. Server 202 may be coupled todata storage for storing recommendation data store 212. An examplecomputer system that may be used as a server 202 is illustrated in FIG.14.

Server 230 may be coupled to Internet 200. An example computer systemthat may be used as a server 230 is illustrated in FIG. 14. Server 230may host a web service client 232. Web service client 232 may beconfigured to programmatically access recommendation engine 210 via webservice interface 206. Note that web service interface 206 does notprovide a “web browser” interface, but instead provides a programmaticinterface via an API through which at least some functionality ofrecommendation engine 210 may be programmatically accessed by webservice client 232. Server 230 may provide a web site accessible toclient(s) via web browsers on device(s) 204, and web service client 232may be configured to access at least some functionality ofrecommendation engine 210 via web service interface 206 to provideaccess to at least some functionality of recommendation engine 210 viathe web site provided by server 230. Device 204 may, for example, berepresentative of a personal desktop or portable computer system, or ofany of various types of personal electronic devices with networkconnectivity such as a portable digital audio file player (e.g., an MP3player), personal digital assistant (PDA), or cell phone. An examplecomputer system that may be used as a device 204 is illustrated in FIG.14. The web site may display a steerable recommender user interface 214as or on one or more pages of the web site. The user may submit requestsfor recommendations to the steerable recommender via the user interface214. A user may, for example, specify an artist name or a song via thesteerable recommender user interface 214, may submit a tag cloud, maymodify a tag in a displayed tag cloud, or may provide some other inputto the steerable recommender via the user interface. The user input maybe sent to the web service client 232 via the Internet 200 in one ormore messages.

To access the recommendation engine 210 provided by the web serviceprovider 202, web service client 232 may, in response to user input tothe steerable recommender user interface 214 displayed on device 204,send a request message to web service interface 206 via Internet 200.Web service provider 202 may then process the request, for example byperforming an indicated function of the recommendation engine 210. Toprocess the request, recommendation engine 210 may access recommendationdata store 212 to find recommendations by comparing the tag clouds ofitems in the data store 312 with a tag cloud provided by the user viathe user interface 314. Web service interface 206 may then returnresults of the processing to the web service client 232 in a responsemessage or messages via Internet 200. The results may include new ormodified recommendations. Web service client 232 then sends appropriateinformation to steerable recommender user interface 214 so that the userinterface 214 is updated to reflect the information, for example bydisplaying the new or modified recommendations.

While FIG. 2 shows one server 230, one web service client 232, and onedevice 204, there may be multiple servers 230 each hosting one or moreweb service clients 232, and there may be multiple devices 204 eachincluding a steerable recommender user interface 214. Further, whileFIG. 2 shows one instance of recommendation engine 210 and onerecommendation data store 212, there may be multiple instances ofrecommendation engine 210 and multiple data stores 212. Further,different data stores 212 may be implemented that store recommendationinformation for different categories of items, or differentrecommendation information for the same category of item.

FIG. 3 is a block diagram that illustrates a steerable recommender and auser interface to the steerable recommender implemented on one device,according to some embodiments. In these embodiments, a device 304 mayinclude an instance of recommendation engine 310 and an instance ofsteerable recommender user interface 314. An example computer systemthat may be used as a device 304 is illustrated in FIG. 14. Steerablerecommender user interface 314 may, for example, be implemented as apage or pages displayable on or by a web browser. Alternatively,steerable recommender user interface 314 may be implemented as or on oneor more display pages of some other software program. The user maysubmit requests for recommendations to the steerable recommender via theuser interface 314. A user may, for example, specify an artist name or asong via the steerable recommender user interface 314, may submit a tagcloud, may modify a tag in a displayed tag cloud, or may provide someother input to the steerable recommender via the user interface. Theuser input may be provided to the recommendation engine 310.Recommendation engine 310 may then process the information to generateresults. To process the request, recommendation engine 310 may accessrecommendation data store 312 to find recommendations by comparing thetag clouds of items in the data store 312 with a tag cloud provided bythe user via the user interface 314. Recommendation data store 312 maybe stored locally, or alternatively may be stored remotely and accessedvia a network. The results may include new or modified recommendations.The steerable recommender user interface 314 may be updated to reflectthe results, for example by displaying the new or modifiedrecommendations.

In embodiments of the steerable recommender, each item may be describedby a set of textual words or phrases, collectively referred to herein astags. These descriptive tags may come from text mining the web, socialannotations, auto-tagging based upon content analysis, expertannotation, etc. FIG. 4 is a block diagram that illustrates collectingitem information for a steerable recommender, according to someembodiments. A system 402 may include one or more steerable recommenderdata collectors 416 that are configured to collect item information fromone or more network sources 406 via a network 400. Examples of networksources 406 may include, but or not limited to, text mining web sitesthat include social annotations, expert opinions, product reviews, andso on. An example computer system that may be used as system 402 isillustrated in FIG. 14. Steerable recommender data collector(s) 416 mayprocess the collected item information and store tags and otherinformation according to the items in recommendation data store 412.While this data collection may be performed initially to generate aninitial data store 412, data collectors 416 may periodically oraperiodically collect additional information about items or collectinformation about new items via the network 400, process theinformation, and store the processed information to the data store 412.

In addition to or instead of collecting item information from networksources 406, a data collector may collect, process and store iteminformation from one or more other sources 408. An example of anothersource may be auto-tagging based upon content analysis. In this case,content of an item (e.g., of a book, song, or album) may beprogrammatically analyzed to automatically generate tags for the item.Another example may be direct user input of descriptive tags forparticular items via a steerable recommender management interface.

After collection and processing of the item information related to a setof items, the tags thus generated for the items may be weighted basedupon their descriptive content, with more descriptive tags given moreweight than less descriptive tags. In one embodiment, a standardweighting function, such as term frequency-inverse document frequency(TF-IDF), may be used to determine these weights. The set of weightedtags for an item may be referred to as the item's tag cloud. Informationon a collection of many items of a particular category of item,including but not limited to the items' tag clouds, may be stored to therecommendation data store 412. In one embodiment, a data collectorcomponent 416 of the steerable recommender may perform acquisition,processing, storing, and maintenance (e.g., updating) of the iteminformation in the data store 412.

FIG. 5 illustrates a method for constructing and maintaining a datastore of information including descriptive tags and tag cloudinformation according to one embodiment. As indicated at 500,descriptive information for items may be collected from one or moresources. In one embodiment, one or more steerable recommender datacollectors may collect item information from one or more networksources. Examples of network sources may include, but or not limited to,text mining web sites that include social annotations, expert opinions,product reviews, and so on. In addition to or instead of collecting iteminformation from network sources, a data collector may collect, processand store item information from one or more other sources. An example ofanother source may be auto-tagging based upon content analysis. Anotherexample may be direct user input of tags for particular items via asteerable recommender management interface.

As indicated at 502, descriptive tags may be extracted from thecollected information. The descriptive tags may include meaningful wordsor phrases that describe the items. One or more descriptive tags may beextracted for each item. As indicated at 504, weights may be determinedfor the tags, and tag clouds including the tags and associated weightsmay be generated for the items. To emphasize words that are moredescriptive, each term may be weighted using a weighting function. Inone embodiment, the standard text retrieval weighting function TF-IDFmay be used. This weighting function gives more weight to tags thatoccur more frequently for a particular item when compared to thefrequency of the tags across all items. Other weighting functions ormethods of weighting tags may be used in other embodiments. The set ofone or more weighted tags for an item may be referred to as an item'stag cloud, textual aura, or simply aura. A tag cloud thus includes atleast the descriptive tags and the associated weights for the tags. Asindicated at 506, the tag clouds may be stored to a data store, andassociated with respective items in the data store.

While this data collection may be performed initially to generate aninitial data store, additional information for items may periodically oraperiodically be collected and processed according to elements 500through 506, and/or information about new items may be collectedaccording to elements 500 through 506, as indicated by the dashed linein FIG. 5.

FIG. 6 illustrates a method for determining a set of recommended itemsfrom the descriptive information for a specified item, according to oneembodiment. As indicated at 600, a steerable recommender engine mayreceive information specifying an item or a tag cloud. For example, auser, via a user interface to the steerable recommender, may requestrecommendations for items similar to a particular item that the userlikes. Alternatively, the user may select an item via the userinterface, and a request for recommendations related to that item may beautomatically generated for the user and submitted to the steerablerecommender engine. In addition, a tag cloud for a particular item maybe displayed on the user interface, and the user may modify the tagcloud, for example by interactively changing the weight of a particulartag, or by adding or removing a tag. The modification may automaticallygenerate a request for updated recommendations corresponding to themodified tag cloud. Thus, the information received by the recommendationengine in response to a generated request may include informationidentifying the current state of the tag cloud, for example identifyingthe tags currently in the cloud and the current weights of the tags inthe cloud. Other methods of generating a request for recommendations arepossible and contemplated.

Note that the request for recommendations related to a particular itemmay, but does not necessarily, include information related to the tagcloud for the item. For example, the request may only identify the item,and the recommendation engine may obtain the tag cloud for the item fromthe data store, or from some other location if the tag cloud is not inthe data store. In one embodiment, if there is no tag cloud for an item,the recommendation engine may dynamically generate a tag cloud for theitem, for example according to the method illustrated in FIG. 5.

In another scenario, the user may submit a custom tag cloud notassociated with any particular item to the steerable recommender via theuser interface to request recommendations related to items whose tagclouds are most similar to the custom tag cloud.

As indicated at 602, a set of other items for which descriptive tagsmost closely match a set of descriptive tags of the specified item ortag cloud may be identified. If the request specifies a tag cloudrelated to an item and the current state of the tag cloud according tothe user's preference (e.g., the current set of tags and associatedweights for the tag cloud as possibly modified by the user), or if therequest specifies a custom tag cloud not related to a particular item,then the tag cloud specified by the request may be used to identifysimilar items. Otherwise, if the request only specifies an item, thenthe steerable recommender engine may obtain a tag cloud for the item, asindicated above, and use that tag cloud to identify similar items.

In one embodiment, the recommendation engine may use standard vectorspace distance calculations, for example the cosine distance between thetag clouds, to determine similarity of the specified tag cloud to tagclouds of items in the data store. In one embodiment, the results of afind similar operation may be filtered by a recommendation enginecomponent of the steerable recommender to optimize relevance, noveltyand familiarity in accordance with specified preferences of the user.The results generated is a set or list of items that are similar to thespecified item according to comparisons of the tag clouds, or a set orlist of items whose tag clouds are similar to a specified custom tagcloud if the user has submitted a custom tag cloud not related to aparticular item. A value indicating the determined strength of thesimilarity to the specified item according to the tag clouds may beincluded with each item. At least a subset of the list of items, and theassociated strength of similarity value, may be displayed to the userinterface. The user interface may include a scrollbar or other userinterface element that allows a user to view additional items on thelist if all the items cannot be displayed in the space provided. Oneembodiment may provide a similarity threshold that filters the list sothat only items whose strength of similarity value is above thethreshold are included in the list. One embodiment may provide a countthreshold so that only a specified number of most similar items areincluded in the list. In some embodiments, the thresholds may beuser-specified via the user interface.

In addition to filtering for similarity, some embodiment may provide oneor more other filters, for example filters for novelty and familiarity.The user interface may provide methods for the user to specify valuesand/or settings for these filters. A novelty filter may be provided thatfilters recommendations so that items that are not already known by theuser are recommended. For example, a music store recommender may trackwhat items the user has already purchased or listened to. Therecommender, via the novelty filter, may ensure that recommendations forthe user only include items that are not in the set of previouslypurchased or listened to items. A familiarity filter may be providedthat filters recommendations so that at least some items that arealready known by the user are recommended, if possible. This may beimportant for a new user that may not have confidence in therecommender. By including some items in a recommendation list that thenew user is likely to be familiar with, the user may gain someconfidence and trust in the recommender. If a recommendation includessome items that the user already knows and likes, the user may be morelikely to trust the recommender.

In one embodiment, the recommender may be tuned using the filters sothat recommendation lists include a mix of novel items and familiaritems. The ratio of novel to familiar items may change over time; as theuser gains more confidence in the recommender, the amount of novel itemscompared to familiar items in recommendation lists may be increased.

FIG. 7 illustrates a method for generating and displayingrecommendations in response to user input, according to one embodiment.As indicated at 700, a steerable recommender may receive user input, viaa steerable recommender user interface, specifying a tag cloud. The tagcloud may include one or more tags and the respective weights for thetags. FIGS. 11 through 13 illustrate exemplary user interfaces to asteerable recommender. For example, a user, via the user interface, mayrequest recommendations for items similar to a particular item that theuser likes. Alternatively, the user may simply select an item via theuser interface. In addition, a tag cloud for a particular item may bedisplayed on the user interface, and the user may modify the tag cloud,for example by interactively changing the weight of a particular tag, orby adding or removing a tag. As another alternative, the user may submita custom tag cloud not associated with any particular item to thesteerable recommender via the user interface. Other methods of acceptinguser input via a user interface specifying a tag cloud and relatedinformation are possible and contemplated.

Note that the user input may, but does not necessarily, retrieveinformation related to the tag cloud from information currentlydisplayed on the user interface. For example, the user input may onlyidentify an item, and the steerable recommender may obtain the tag cloudand related information from the data store, or from some other locationif the tag cloud is not in the data store. In one embodiment, if thereis no tag cloud for a specified item, the recommendation engine maydynamically generate a tag cloud for the item in response to user input,for example according to the method illustrated in FIG. 5.

As indicated at 702, a set of items for which associated tag clouds aremost similar to the specified tag cloud according to the tags andassociated weights may be identified. See, for example, element 602 ofFIG. 6 and the related discussion above.

As indicated at 704, information may be displayed, to the userinterface, identifying the set of items and indicating similarity to thespecified tag cloud. The displayed information may include a set or listof items that are similar to the specified item according to comparisonsof the tag clouds, or a set or list of items whose tag clouds aresimilar to a specified custom tag cloud, if the user has submitted acustom tag cloud not related to a particular item. A value indicatingthe strength of the similarity to the specified item may be displayedwith each item. At least a subset of the list of items, and theassociated strength of similarity value, may be displayed to the userinterface. The user interface may include a scrollbar or other userinterface element that allows a user to view additional items on thelist if all the items cannot be displayed in the space provided. Oneembodiment may provide a similarity threshold that filters the list sothat only items whose strength of similarity value is above thethreshold are included in the list. One embodiment may provide a countthreshold so that only a specified number of most similar items areincluded in the list. Other embodiments may include other user interfaceelements that allow a user to otherwise manipulate the list.

In addition to filtering for similarity, some embodiment may provide oneor more other filters, for example filters for novelty and familiarity.The user interface may provide methods for the user to specify valuesand/or settings for these filters. A novelty filter may be provided thatfilters recommendations so that items that are not already known by theuser are recommended. A familiarity filter may be provided that filtersrecommendations so that at least some items that are already known bythe user are recommended, if possible.

In one embodiment, a user may select a displayed item in the list ofrecommended items, and the tag cloud for that item may then bedisplayed. In one embodiment, in response to the user selecting an itemfrom the list, in addition to displaying the tag cloud for the selecteditem, the recommendation list may automatically be updated to displayitems recommended according to the tag cloud of the selected item. Inone embodiment, a user may modify a currently displayed tag cloud viathe user interface, for example by interactively changing the weight ofa tag, or by adding or removing a tag, and the list of recommended itemsmay be automatically updated to reflect the user's modification of thetag cloud.

FIG. 8 illustrates a method for generating and displaying modifiedrecommendations in response to user input modifying a tag cloud,according to one embodiment. FIGS. 11 through 13 illustrate exemplaryuser interfaces to a steerable recommender. As indicated at 800, asteerable recommender may receive user input, via a user interface tothe steerable recommender, indicating a modification to a displayed tagcloud. For example, in one embodiment, the tag cloud (either a tag cloudrelated to an item or a user's custom tag cloud not related to anyparticular item) may be represented on a display screen such that higherweighted tags in the displayed tag cloud are shown in a larger font. Theuser may use a cursor control device, or in some embodiments thekeyboard, to adjust or manipulate the tags in the tag cloud displayed onthe user interface. For example, the user may, via the user interface,add new tags, remove tags, or increase or decrease the weights of thetags via a cursor control device click-and-drag to resize the tags. Inone embodiment, the user may make the weight of a tag go negative,indicating that the user wants to avoid items with that tag. In oneembodiment, the user interface may allow a user to indicate that aparticular tag or tags must appear in the tag cloud of a recommendeditem. In other words, only items tagged with a tag or tags so indicatedwill be recommended.

As indicated at 802, a different set of items for which associated tagclouds are most similar to the modified tag cloud may be identified.See, for example, element 602 of FIG. 6 and the related discussionabove.

As indicated at 804, information may be displayed, to the userinterface, identifying the different set of items and indicatingsimilarity of the items to the modified tag cloud. In one embodiment,the list of recommended items may be automatically updated to reflectthe user's modification of the tag cloud.

FIG. 9 illustrates a method for displaying information as to why aparticular recommendation was made, according to one embodiment. Asindicated at 900, a steerable recommender may receive user input, via auser interface to the steerable recommender, requesting information onwhy an item was recommended. In one embodiment, a user interface elementmay be associated with each item in the displayed list of recommendeditems. A user may select this interface element to request informationon why the particular item was recommended. See, for example, element1206 of FIG. 12 and element 1306 of FIG. 13.

As indicated at 902, information may be displayed, to the userinterface, indicating why the item was recommended in response to theuser input. In one embodiment, since recommendations made by thesteerable recommender are based on the similarity between auser-specified tag cloud and the tag clouds of the recommended item(s),a more detailed explanation of why an item was recommended may beprovided by displaying how the two tag clouds overlap. See, for example,FIGS. 11.

Steerable Recommender and User Interface Examples

In this section, an example embodiment of a web-based steerablerecommender application, and examples of a user interface to thesteerable recommender, that together provide transparent and steerablerecommendations for music and musical artists are described. Thesteerable recommender, via the user interface, may provide a detailedexplanation about why a particular item was recommended, and may allow auser to steer the recommendations based upon attributes of the musicand/or artist. Note that this embodiment is described as an example, andis not intended to be limiting. Embodiments of the steerable recommendermay be directed at other categories of items, and variations on theprovided examples of the user interface are possible and contemplated.

FIG. 10 graphically illustrates examples of tag clouds for severalexample artists A through G according to one embodiment. In the exampleembodiment, each musical artist is annotated by a set of descriptivewords and phrases, or tags, which, when weighted, collectively form atag cloud (tags and associated weights) for the musical artist. Thesource of these tags may, for example, be from text mining the web, fromsocial annotations, autotagging based upon content analysis, expertannotation, etc. Some tags such as rock and alternative are commonlyapplied to many musical artists, and therefore are not very descriptive,while tags such as shoegaze and grindcore are less frequently appliedand are thus more discriminating. To emphasize tags that are moredescriptive, each tag may be weighted using a weighting function. In oneembodiment, the standard text retrieval weighting function TF-IDF may beused to weight the tags. This weighting function gives more weight totags that occur more frequently for a particular item when compared tothe frequency of the tags across all items. Other weighting functions ormethods of weighting tags may be used in other embodiments. The set ofweighted tags for an item may be referred to as an item's tag cloud,textual aura, or simply aura. This tag cloud may be displayed to a userinterface as a representation of a musical artist. In one embodiment,the similarity between two musical artists may be determined as thecosine similarity between the weighted tags in tag clouds for theartists. As in the examples shown in FIG. 10, the relative font size ofa tag may indicate the tag's respective weight, with tags in largerfonts for a particular artist representing tags given more weight forthe respective artist. Other methods than font size, such as differentcolors, shades, fonts, or case, may be used in some embodiments tographically and/or textually provide additional information about thetags and/or tag clouds. For example, in one embodiment, a red color fora tag may indicate that the tag is a “negative” tag.

Transparency

A key to the success of a recommender is to gain the trust of its users.One way to gain this trust is to provide a detailed explanation of whyan item was recommended. However, most conventional music recommendersrely on collaborative filtering techniques to offer recommendations.These systems cannot offer any more detailed explanation of why an itemwas recommended beyond the simplistic “people who liked artist X, alsoliked artist Y.” These opaque recommendations do little to garner thetrust of the user.

Since recommendations made by embodiments of the steerable recommenderare based on the similarity between the tag clouds of a user-preferreditem and the recommended item(s), embodiments may provide a moredetailed explanation of why an item was recommended by displaying howthe two tag clouds overlap. FIG. 11 shows an example tag cloud includingthe overlapping or common tags for the artists Muse and Radiohead,according to one embodiment. Only words common to the two artists aredisplayed. The tags in this tag cloud may be weighted by the strength ofthe overlap between the two clouds. In this example, the size of thefont used for a tag may be determined by the weight of the tag tovisually indicate the strength of the overlap. Thus, tags with a higherweight and stronger overlap are displayed in a larger font size thantags with lower weight and weaker overlap to visually indicate therelative weights of the tags. Other methods than font size may be usedto graphically and/or textually indicate the tag weight and overlapmetrics.

Some embodiments may provide one or more selectable user interface itemsvia which the user may request additional information about arecommendation. For example, in one embodiment, there may be a “Why?”user interface element displayed by each recommendation. The user mayselect this item to display information as to why the recommendation wasmade, e.g. information on how the tag cloud of this item and the tagcloud of the item on which the recommendation was based interact.

Steerability

When a user receives a set of recommendations based upon a seed item,e.g. a musical artist, the user may decide that the steerablerecommender is giving too much weight to a certain aspect of the seeditem, and too little weight to another. In conventional recommenders,there is little if anything that the user can do guide the recommendertoward aspects that the user finds desirable. Using an embodiment of thesteerable recommender, the user has more control over the aspects thatthe recommender uses to generate the recommendations.

To steer recommendations with an embodiment of the steerablerecommender, a user may interact with a tag cloud for a seed artist. Theseed artist is an initial artist from which a user may start a searchfor recommendations. In one embodiment, a user may also start with aseed tag cloud to locate artists according to the user's taste. The usermay, for example, add tags, remove tags or adjust the weight of any tagin the tag cloud. Whenever the user makes changes, the set ofrecommended artists is updated to include the artists that best matchthe new tag cloud. For example, a fan of 60s psychedelic guitarist JimiHendrix could adjust the Jimi Hendrix tag cloud to give more weight tothe guitar tag and less weight to the 60s and the psychedelic tags tosteer the recommender toward guitarists that sound like Jimi Hendrix,and away from other 60s psychedelia artists. The recommender wouldrespond by recommending artists more like Stevie Ray Vaughan and lesslike Janis Joplin or The Doors.

FIG. 12 illustrates an example of a steerable recommender user interfacedirected at musical artists according to one embodiment. In thisexample, the user has started with a tag cloud based upon the top tagsfor the artist Coldplay. The user has also added the artist Muse to thetag cloud. This has the effect of implicitly including all of the tagsfor Muse in the tag cloud. As indicated at 1202, a user may add tags orartists to the tag cloud 1200 by clicking on the tags in the right handpanel. As indicated at 1204, a user can increase or decrease the weightof an individual tag by dragging it with the cursor control device toincrease or decrease its size; increasing the size increases the weight,while decreasing the size decreases the weight. In one embodiment, a tagthat is shrunk below the size of zero begins to grow again as a negativetag that acts as a filter in the returned recommendations 1208. Anegative tag may, for example, be indicated by coloring the tagdifferently. For example, in one embodiment, negative tags may becolored red. Tags with negative weights act as filters—artists taggedwith a negatively weighted tag will not be recommended.

In one embodiment, the user interface may allow a user to indicate thata particular tag or tags must appear in the tag cloud of a recommendeditem. In other words, in this example, only artists tagged with a tag ortags so indicated will be recommended.

A user interface element may be associated with each recommendation 1208which the user may select to get more information on why the particularitem was recommended, as indicated at 1206. In one embodiment, sincerecommendations made by the steerable recommender are based on thesimilarity between a user-specified tag cloud and the tag clouds of therecommended item(s), a more detailed explanation of why an item wasrecommended may be provided by displaying how the two tag cloudsoverlap. See, for example, FIG. 11.

Whenever the tag cloud 1200 is modified, a new set of artists with tagclouds most similar to the modified tag cloud 1200 may be identified,and the user interface may display an updated list of recommendations1208 corresponding to the new set of artists. These are the artists thatmost closely match the tag cloud 1200 that the user has constructed ormodified. In various embodiments, the user may, for example, listen to arecommended artist, view photos of the artist, inspect the tag cloud ofan artist, or rate the artist. The user may then modify the tag cloud1200 to steer the recommendations 1208 away from undesirable artists andtoward more relevant or desirable artists. This dynamic, iterativeapproach to recommendations puts the user in control of the recommender,in contrast to conventional recommenders that use collaborativefiltering and that typically gives a user little or no control.

FIG. 13 illustrates another example of a steerable recommender userinterface directed at musical artists, according to one embodiment. Inthis example, the user has started with a tag cloud based upon the toptags for the artist Jimi Hendrix. The indicated user interface elements1300, 1302, 1304, 1306 and 1308 are similar to the user interfaceelements 1200, 1202, 1204, 1206 and 1208, respectively, of FIG. 12.

Example System

Various components of embodiments of a method and apparatus forgenerating steerable recommendations as described herein, for example arecommendation engine, a steerable recommender user interface, and/or asteerable recommender data collector, may be executed on one or morecomputer systems, which may interact with various other devices. Onesuch computer system is illustrated by FIG. 14. In the illustratedembodiment, computer system 1400 includes one or more processors 1410coupled to a system memory 1420 via an input/output (I/O) interface1430. Computer system 1400 further includes a network interface 1440coupled to I/O interface 1430, and one or more input/output devices1450, such as cursor control device 1460, keyboard 1470, audio device1490, and display(s) 1480. In some embodiments, it is contemplated thatembodiments may be implemented using a single instance of computersystem 1400, while in other embodiments multiple such systems, ormultiple nodes making up computer system 1400, may be configured to hostdifferent portions, components, or instances of embodiments. Forexample, in one embodiment some elements may be implemented via one ormore nodes of computer system 1400 that are distinct from those nodesimplementing other elements.

In various embodiments, computer system 1400 may be a uniprocessorsystem including one processor 1410, or a multiprocessor systemincluding several processors 1410 (e.g., two, four, eight, or anothersuitable number). Processors 1410 may be any suitable processor capableof executing instructions. For example, in various embodiments,processors 1410 may be general-purpose or embedded processorsimplementing any of a variety of instruction set architectures (ISAs),such as the x86, PowerPC, SPARC, or MIPS ISAs, or any other suitableISA. In multiprocessor systems, each of processors 1410 may commonly,but not necessarily, implement the same ISA.

In some embodiments, at least one processor 1410 may be a graphicsprocessing unit. A graphics processing unit or GPU may be considered adedicated graphics-rendering device for a personal computer,workstation, game console or other computer system. Modern GPUs may bevery efficient at manipulating and displaying computer graphics, andtheir highly parallel structure may make them more effective thantypical CPUs for a range of graphical algorithms. For example, agraphics processor may implement a number of graphics primitiveoperations in a way that makes executing them much faster than drawingdirectly to the screen with a host central processing unit (CPU). TheGPU(s) may implement one or more application programmer interfaces(APIs) that permit programmers to invoke the functionality of theGPU(s). Suitable GPUs may be commercially available from vendors such asNVIDIA Corporation, ATI Technologies, and others.

System memory 1420 may be configured to store program instructionsand/or data accessible by processor 1410. In various embodiments, systemmemory 1420 may be implemented using any suitable memory technology,such as static random access memory (SRAM), synchronous dynamic RAM(SDRAM), nonvolatile/Flash-type memory, or any other type of memory. Inthe illustrated embodiment, program instructions and data implementingdesired functions, such as those described above for various embodimentsof a method and apparatus for generating steerable recommendations, areshown stored within system memory 1420 as program instructions 1425 anddata storage 1435, respectively. In other embodiments, programinstructions and/or data may be received, sent or stored upon differenttypes of computer-accessible media or on similar media separate fromsystem memory 1420 or computer system 1400. Generally speaking, acomputer-accessible medium may include storage media or memory mediasuch as magnetic or optical media, e.g., disk or CD/DVD-ROM coupled tocomputer system 1400 via I/O interface 1430. Program instructions anddata stored via a computer-accessible medium may be transmitted bytransmission media or signals such as electrical, electromagnetic, ordigital signals, which may be conveyed via a communication medium suchas a network and/or a wireless link, such as may be implemented vianetwork interface 1440.

In one embodiment, I/O interface 1430 may be configured to coordinateI/O traffic between processor 1410, system memory 1420, and anyperipheral devices in the device, including network interface 1440 orother peripheral interfaces, such as input/output devices 1450. In someembodiments, I/O interface 1430 may perform any necessary protocol,timing or other data transformations to convert data signals from onecomponent (e.g., system memory 1420) into a format suitable for use byanother component (e.g., processor 1410). In some embodiments, I/Ointerface 1430 may include support for devices attached through varioustypes of peripheral buses, such as a variant of the Peripheral ComponentInterconnect (PCI) bus standard or the Universal Serial Bus (USB)standard, for example. In some embodiments, the function of I/Ointerface 1430 may be split into two or more separate components, suchas a north bridge and a south bridge, for example. In addition, in someembodiments some or all of the functionality of I/O interface 1430, suchas an interface to system memory 1420, may be incorporated directly intoprocessor 1410.

Network interface 1440 may be configured to allow data to be exchangedbetween computer system 1400 and other devices attached to a network,such as other computer systems, or between nodes of computer system1400. In various embodiments, network interface 1440 may supportcommunication via wired or wireless general data networks, such as anysuitable type of Ethernet network, for example; viatelecommunications/telephony networks such as analog voice networks ordigital fiber communications networks; via storage area networks such asFibre Channel SANs, or via any other suitable type of network and/orprotocol.

Input/output devices 1450 may, in some embodiments, include one or moredisplay terminals, keyboards, keypads, touchpads, scanning devices,voice or optical recognition devices, or any other devices suitable forentering or retrieving data by one or more computer system 1400.Multiple input/output devices 1450 may be present in computer system1400 or may be distributed on various nodes of computer system 1400. Insome embodiments, similar input/output devices may be separate fromcomputer system 1400 and may interact with one or more nodes of computersystem 1400 through a wired or wireless connection, such as over networkinterface 1440.

As shown in FIG. 14, memory 1420 may include program instructions 1425,configured to implement embodiments of method and apparatus forgenerating steerable recommendations, and data storage 1435, comprisingvarious data accessible by program instructions 1425. In one embodiment,program instructions 1425 may include software elements of embodimentsof a method and apparatus for generating steerable recommendations, asillustrated in the above Figures. Data storage 1435 may include datathat may be used in embodiments. In other embodiments, other ordifferent software elements and data may be included.

Those skilled in the art will appreciate that computer system 1400 ismerely illustrative and is not intended to limit the scope of a methodand apparatus for generating steerable recommendations as describedherein. In particular, the computer system and devices may include anycombination of hardware or software that can perform the indicatedfunctions, including computers, network devices, internet appliances,PDAs, wireless phones, pagers, etc. Computer system 1400 may also beconnected to other devices that are not illustrated, or instead mayoperate as a stand-alone system. In addition, the functionality providedby the illustrated components may in some embodiments be combined infewer components or distributed in additional components. Similarly, insome embodiments, the functionality of some of the illustratedcomponents may not be provided and/or other additional functionality maybe available.

Those skilled in the art will also appreciate that, while various itemsare illustrated as being stored in memory or on storage while beingused, these items or portions of them may be transferred between memoryand other storage devices for purposes of memory management and dataintegrity. Alternatively, in other embodiments some or all of thesoftware components may execute in memory on another device andcommunicate with the illustrated computer system via inter-computercommunication. Some or all of the system components or data structuresmay also be stored (e.g., as instructions or structured data) on acomputer-accessible medium or a portable article to be read by anappropriate drive, various examples of which are described above. Insome embodiments, instructions stored on a computer-accessible mediumseparate from computer system 1400 may be transmitted to computer system1400 via transmission media or signals such as electrical,electromagnetic, or digital signals, conveyed via a communication mediumsuch as a network and/or a wireless link. Various embodiments mayfurther include receiving, sending or storing instructions and/or dataimplemented in accordance with the foregoing description upon acomputer-accessible medium. Accordingly, the present invention may bepracticed with other computer system configurations.

CONCLUSION

Various embodiments may further include receiving, sending or storinginstructions and/or data implemented in accordance with the foregoingdescription upon a computer-accessible medium. Generally speaking, acomputer-accessible medium may include storage media or memory mediasuch as magnetic or optical media, e.g., disk or DVD/CD-ROM, volatile ornon-volatile media such as RAM (e.g. SDRAM, DDR, RDRAM, SRAM, etc.),ROM, etc., as well as transmission media or signals such as electrical,electromagnetic, or digital signals, conveyed via a communication mediumsuch as network and/or a wireless link.

The various methods as illustrated in the Figures and described hereinrepresent examples of embodiments of methods. The methods may beimplemented in software, hardware, or a combination thereof. The orderof method may be changed, and various elements may be added, reordered,combined, omitted, modified, etc.

Various modifications and changes may be made as would be obvious to aperson skilled in the art having the benefit of this disclosure. It isintended that the invention embrace all such modifications and changesand, accordingly, the above description to be regarded in anillustrative rather than a restrictive sense.

1. A computer-implemented method, comprising: displaying a tag cloud inresponse to user input specifying the tag cloud, wherein the tag cloudcomprises one or more tags, wherein each tag specifies a descriptiveword or phrase; determining a set of recommended items from a collectionof items in response to the user input, wherein the set of recommendeditems is determined according to similarity of tag clouds associatedwith the items in the collection to the displayed tag cloud, wherein theset of recommended items comprises items for which a determinedsimilarity value is above a similarity threshold; and displaying the setof recommended items.
 2. The computer-implemented method as recited inclaim 1, further comprising: receiving user input modifying thedisplayed tag cloud; determining a modified set of recommended itemsfrom the collection of items in response to the user input modifying thedisplayed tag cloud; and displaying the modified set of recommendeditems.
 3. The computer-implemented method as recited in claim 2, whereinthe user input modifying the displayed tag cloud increases or decreasesa weight associated with a particular tag in the tag cloud, whereinincreasing the weight increases an influence of the associated tag whendetermining the modified set of recommended items, and whereindecreasing the weight decreases the influence of the associated tag whendetermining the modified set of recommended items.
 4. Thecomputer-implemented method as recited in claim 2, wherein the userinput modifying the displayed tag cloud adds or removes a tag from thetag cloud.
 5. The computer-implemented method as recited in claim 1,further comprising: receiving user input selecting one of the displayedrecommended items; determining another set of recommended items from thecollection of items corresponding to the selected recommended item inresponse to the user input selecting the recommended item; anddisplaying the other set of recommended items.
 6. Thecomputer-implemented method as recited in claim 1, further comprising:receiving user input selecting one of the displayed recommended items;and displaying information related to why the selected item wasrecommended in response to the user input selecting the recommendeditem.
 7. The computer-implemented method as recited in claim 6, whereinsaid displayed information indicates how the tag cloud associated withthe selected recommended item overlaps the displayed tag cloud.
 8. Thecomputer-implemented method as recited in claim 1, further comprisingfiltering the set of recommended items so that items that are novel tothe user are displayed.
 9. The computer-implemented method as recited inclaim 1, further comprising filtering the set of recommended items sothat at least some items that are familiar to the user are displayed.10. A system comprising: at least one processor; a display device; and amemory storing program instructions, wherein the program instructionsare executable by the at least one processor to: display a tag cloud toa user interface on the display device in response to user inputspecifying the tag cloud, wherein the tag cloud comprises one or moretags, wherein each tag specifies a descriptive word or phrase; determinea set of recommended items from a collection of items in response to theuser input, wherein the program instructions are executable by the atleast one processor to determine the set of recommended items accordingto similarity of tag clouds associated with the items in the collectionto the displayed tag cloud, wherein the set of recommended itemscomprises items for which a determined similarity value is above asimilarity threshold; and display the set of recommended items to theuser interface.
 11. The system as recited in claim 10, wherein theprogram instructions are executable by the at least one processor to:receive user input modifying the displayed tag cloud; determine amodified set of recommended items from the collection of items inresponse to the user input modifying the displayed tag cloud; anddisplay the modified set of recommended items.
 12. The system as recitedin claim 11, wherein the user input modifying the displayed tag cloudincreases or decreases a weight associated with a particular tag in thetag cloud, wherein increasing the weight increases an influence of theassociated tag when determining the modified set of recommended items,and wherein decreasing the weight decreases the influence of theassociated tag when determining the modified set of recommended items.13. The system as recited in claim 11, wherein the user input modifyingthe displayed tag cloud adds or removes a tag from the tag cloud. 14.The system as recited in claim 10, wherein the program instructions areexecutable by the at least one processor to: receive user inputselecting one of the displayed recommended items; determine another setof recommended items from the collection of items corresponding to theselected recommended item in response to the user input selecting therecommended item; and display the other set of recommended items. 15.The system as recited in claim 10, wherein the program instructions areexecutable by the at least one processor to: receive user inputselecting one of the displayed recommended items; and displayinformation related to why the selected item was recommended in responseto the user input selecting the recommended item, wherein said displayedinformation indicates how the tag cloud associated with the selectedrecommended item overlaps the displayed tag cloud.
 16. Acomputer-readable storage medium storing program instructions, whereinthe program instructions are computer-executable to implement:displaying a tag cloud in response to user input specifying the tagcloud, wherein the tag cloud comprises one or more tags, wherein eachtag specifies a descriptive word or phrase; determining a set ofrecommended items from a collection of items in response to the userinput, wherein the set of recommended items is determined according tosimilarity of tag clouds associated with the items in the collection tothe displayed tag cloud, wherein the set of recommended items comprisesitems for which a determined similarity value is above a similaritythreshold; and displaying the set of recommended items.
 17. Thecomputer-readable storage medium as recited in claim 16, wherein theprogram instructions are computer-executable to implement: receivinguser input modifying the displayed tag cloud; determining a modified setof recommended items from the collection of items in response to theuser input modifying the displayed tag cloud; and displaying themodified set of recommended items.
 18. The computer-readable storagemedium as recited in claim 17, wherein the user input modifying thedisplayed tag cloud increases or decreases a weight associated with aparticular tag in the tag cloud, wherein increasing the weight increasesan influence of the associated tag when determining the modified set ofrecommended items, and wherein decreasing the weight decreases theinfluence of the associated tag when determining the modified set ofrecommended items.
 19. The computer-readable storage medium as recitedin claim 16, wherein the program instructions are computer-executable toimplement: receiving user input selecting one of the displayedrecommended items; determining another set of recommended items from thecollection of items corresponding to the selected recommended item inresponse to the user input selecting the recommended item; anddisplaying the other set of recommended items.
 20. The computer-readablestorage medium as recited in claim 16, wherein the program instructionsare computer-executable to implement: receiving user input selecting oneof the displayed recommended items; and displaying information relatedto why the selected item was recommended in response to the user inputselecting the recommended item, wherein said displayed informationindicates how the tag cloud associated with the selected recommendeditem overlaps the displayed tag cloud.